Speaking-telephone



(no l lodem- R. BICKB MEYER. ZSheets-Sheet 1v Speaking Telephone.

No. 230,698. Patented Aug. 3,1880.

Witnesses Inventor: W :4 5

Z. %WML NJETEii FHOIO-LIYHUGRAPNEH, WASHINGTON, D C.

(No Model.) R EIGK-EMEYER. 2 S heets Sheet '2.

7 Speaking Telephone. No. 230,698. Patented Aug. 3,1880.

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NPETERS. FHOTO-LITHOGRAPNER, WASHINGTON D C 1 EEtcE.

P TENT RUDOLF EIOKEMEYER, OF YONKERS, NEW YORK.

SPEAKING-TELEPHONE.

SPECIFICATION forming part of Letters Patent No. 230,698, dated August 3, 1880.

Application filed May 10,1880.

To all whom it may concern:

Be it known that I, RUnoLF EIGKEMEYER, of Yonkers, in the State of New York, have invented a new and useful Improvement in Speaking-Tele iihones, of which the following is a specification.

My invention relates to anew form of transmitting-iustrument for the electrical speaking telephone. The instrument embraces a magneto-electric apparatus for generating an electric current by the movement of the armature of a magnet in its magnetic field of force. The power to move the armature may be supplied by a weight or spring or directly by the human hand.

The instrument also embraces a telephonedisk'or vibrating plate to receive the soundwaves, and, by its vibrations under such waves,

to control or vary the power exerted on the armature of the electro-magnet for generating a current in the telephone-circuit. In this instrument the force of the sound-waves falling upon the disk does not act to vary the resistance of an electric circuit through which a current is flowing, nor directly-to move the armature of an electro-magnet, and thus generate a current in a telephone-circuit; but it acts to vary the amount of force exerted by the weight or spring or other source of power upon the armature, and it does this by increasing or diminishing the friction between a revolving wheel and a rod or lever resting against it and connected with the armature by the movement of which the currentis generated.

In the drawings, Figure 1 is a front elevation of an instrument embodying my invention. Fig. 2 is asectional elevation on the line 00 x of Fig. I. Fig. 3 is a sectional elevation on the line m :20 of Fig. 1. Fig. et'is a plan with the mouth-piece and diaphragm shown in section on the line 00 m of Fig. 1. Fig. 5 is a plan with the driving-shaft, key, and mouthpiece removed.- Figs. 6, 7, 8, and 9 are enlarged views, illustrating some of the details of construction.

A is a wooden frame, upon the upright portions of which is mounted a slotted bed-plate A. B is a shaft having hearings in brackets ca, which are screwed to the bed-plate A, and having an enlargement,B, which,in turn, has a V-shapcd friction-groove, o. The shaftB is (No model.)

revolved by a crank-wheel, O, on shaft 0, which carries a pinion, 0, taking into a gearwheel, I), on shaft B. D is the mouthpiece, of the ordinary funnel shape. D is an adjustable rectangular bracket secured to the bedplate A by screws (Z d passing through slots in the horizontal part of the bracket.

Between the perpendicular part ofthe bracket D and the month-piece D is clamped the diaphragm o in such manner that its center is as near as may be in a horizontal plane which, it continued, would bisect the shaft B, and at the same time is in a perpendicular plane which, if continued, would bisect the V-shaped groove 01.

. E is an adjustable plate, secured, to the bedplate A by screws d (l passing through slots in the plate E; and to the plate E is secured by a screw, (1 a rectangular wooden block, F, in the side faces of which are inserted two binding-screws, 8 .9 To the upper face of the block F, by means ofa plate, t, and screws 01 d", is clamped the rear end of a broad spring, 0.

K is a-key fitting nicely in the groove 12 of the shaft B. It is a hinged at one end to the center of the diaphragm, as best shown in Figs. 6 and 7, and near the other to a post,p, the broad base of which rests on spring 0.

J is an induction-coil, held in position in part by having the lower flange of its spool fitted into the block F and in part by a strap, Z.

The core 1 of the induction-coil J consists of a number of pieces of soft iron within a tube, the whole being secured to the lower face of the spring 0, as shown.

M is a permanent magnet made up of several magnetic bars clamped together, as shown, and supported by a bracket, G, which is secured to the adjustable plate E.

Between the bars of the magnet M, at the upper end, is inserted a soft-iron plate, r, the upper portion of which forms a core for a secondinduction-coil, J, the spool of which fits tightly upon the core.

In front of the magnet M is a hard-rubber plate, P, secured to the bracket G by two screws passing through a plate, a, as shown, and in this plate are two binding-screws, s s.

The outer end of the wire of induction-coil J is connected-with the inner end of the wire of induction-coil J by means of binding-screws s 8 which are connected by an independent wire, and the inner end of coil J is connected with the ground by means of binding-screw 8, while the outer end of coil J is connected with the line-wire by means of binding-screw s.

The mode of operation is as follows: The operator speaks at the mouth-piecein the usual manner, and at the same time the crank-wheel is turned. In the normal adjustment of the instrument the motion of the shaft B has a tendency to send the key K downward, carrying with it the post 1), spring 6, and core 1', while the spring 6 has a tendency, and nearly, although not quite, the requisite strength, to carry the key hack to its normal position in the groove, and at the same time lift the core 1, which has a free up-and-down movement within its coil J. This movement creates by induction a current in coils J and J, and consequently in the line-wire. The vibrations of the diaphragm, caused by sound-waves falling upon it, constantly modify the frictional contact between the key K and the groove '0, and there is a corresponding modification in the length and speed of the movements of the core within the coil J. Therefore, while the crank is turned and the operator talks at the mouthpiece, a current traverses the line-wire, varying in strength with the movement of the diaphragm in such manner that the sounds uttered will be reproduced in a proper receiving-instrument.

The adjustment of the plate D is controlled by screws d and d in aprojection from thelower edge of the front face of that plate, the screws (1 entering the bed-plate A, while the screws 01 bear against the edge of the bed-plate A.

A spring, n, which is adjusted by a setscrew, y, maintains the required initial pressure between the key K and the groove '1). This method of regulating the initial pressure relieves the diaphragm from unnecessary strain.

I claim- 1. A transmitting-instrument for the electric telephone in which the sound-waves falling upon the instrument are made to vary the force exerted by a spring, weight, or other source of power to move the armature of an electro-magnet and generate a currentiu a telephonic circuit.

2. The adjustable spring 20, so arranged as to maintain the required initial pressure between the key K and the groove '0, substantially as described.

R. EIGKEMEYER.

Witnesses:

HENRY OSTERI-IELD, GEORGE NARR. 

